Decreasing prevalence of intestinal parasitic infections among school-aged children in Nepal: a systematic review and meta-analysis.

BACKGROUND: In the last two decades there have been several studies describing the prevalence of intestinal parasites in Nepal; however, there is a lack of surveillance data in the country. METHODS: We searched literature in PubMed, MEDLINE, EMBASE, Google Scholar and local peer-reviewed journals published from 1990 to 2015 for studies describing prevalence of intestinal parasites among school-aged children. We conducted meta-regression to understand the trend over time and pooled the prevalence using 'metaprop' command in STATA 12.1. RESULTS: Thirty-one studies examining 12 080 fecal specimens were included. The prevalence of intestinal parasitic infections showed a significantly decreasing trend (OR 0.56; 95% CI 0.43-0.73 for each consecutive 5 years) and was similar in males and females. The pooled prevalence in years 1996-2000, 2001-2005, 2006-2010 and 2011-2015 was 61.1% (95% CI 51.47-70.26), 53.2% (95% CI 20.94-83.99), 32.7% (95% CI 26.57-39.21) and 20.4% (95% CI 15.04-26.25), respectively. The proportion of helminths among total intestinal parasites was higher in rural areas 57.6% (95% CI 43.54-71.61), and proportion of protozoa among total intestinal parasites was higher in urban areas 68.4% (95% CI 63.23-73.62). Poly-parasitism was observed in 7.7% (95% CI 5.57-9.73) of children. CONCLUSION: We observed a significantly decreasing trend in prevalence of intestinal parasitic infections among school-aged children in Nepal over the last two decades.

Trends in prevalence of soil-transmitted helminth and major intestinal protozoan infections among school-aged children in Nepal.

OBJECTIVES: To assess the trends in prevalence of soil-transmitted helminths (STHs), Entamoeba histolytica and Giardia lamblia among school-aged children in Nepal between 1990 and 2015. METHODS: Systematic literature search in PubMed, MEDLINE, EMBASE, Google Scholar and local peer-reviewed journals for papers published between 1990 and December 2015. We conducted metaregression and meta-analyses to pool studies where applicable. RESULTS: Thirty-nine studies that examined a total of 14 729 stool specimens were included in the meta-analyses. The metaregression of prevalence of hookworms, roundworm, and whipworm showed a significantly decreasing trend over time. In or after 2004, the pooled prevalence of hookworm infections was 1.53% (95% CI, 0.73-2.59), of roundworm 4.31% (95% CI, 2.52-6.53) and of whipworm 2.89% (95% CI, 1.33-4.97) vs. 16.54% (95% CI, 7.64-27.97) for hookworm, 25.20% (95% CI, 13.59-38.97) for roundworm and 11.54% (95% CI 4.25-21.76) for whipworm in 1993-2003. E. histolytica and G. lamblia had stable prevalence since early 1990s, with a pooled prevalences of 4.12% (95% CI, 2.73-5.77) and 9.40% (95% CI, 7.15-11.92), respectively. The prevalence of G. lamblia was significantly higher in urban areas. CONCLUSIONS: We observed a sharp decrease in prevalence of STHs among school-aged children in Nepal in the past decade with prevalences dropping below 5% for STHs with no variation in prevalence in rural and urban areas. However, the prevalence of E. histolytica and G. lamblia remained stable over time. These results suggest that school-based deworming programmes rolled out during the study period had an observable impact on prevalence of STHs.